Zirconia Precursor

PVA addition to zirconia precursor solutions resulted in an increase of the membrane pore volume and the pore size compared to samples without PVA. Similar effects were found for titania membranes but at lower temperatures indicating a relatively small thermal stability of these titania membranes. This can be improved by doping with alumina [39,40]. 

The new one-step synthesis in basic medium [9,10] gives rise to sulfeted zirconia (SZ samples) in pure tetragonal phase. This phase is formed alter calcination at relatively low temperature (500-600°C) and is stabilised by the small size of the particles. Their formation is fevoured by both the controlled hydrolysis of zirconia precursor in the sol and the following fest sulfiitation of zirconia oligomers. The Pt-SZ catalysts obtained from these samples show improved... 

Monolithic zirconia networks can also be formed using a similar procedure giving porous 2xQ>2 structures [9]. As the titania and zirconia precursors are miscible, binary inorganic networks of various Ti Zr ratios could be produced [9]. The crystallinity and photocatalytic properties of the mixed material were studied X-ray amorphous materials were produced for Ti Zr ratios of 2 8 to 7 3, and the binary material containing 10% zirconia (the presence of which inhibited crystal transformation to the rutile phase) showed the highest photocatalytic activity for the photodecomposition of sahcylic acid and 2-chlorophenol [9]. 

Zirconia particles were incorporated in the ordered mesoporous material SBA-15 by impregnating the calcined host material with zirconia precursor solutions and subsequent heat treatments. The materials were characterized by XRD, N2-Sorption, TEM and EDX. Different analytical techniques indicate the incorporation of zirconia clusters inside the host structure with particle sizes between 3 and 5 nm, and the existence of a small amount of zirconia particles outside the host structure. According to the XRD pattern, the SBA-15 support stabilizes the tetragonal phase and the particle size up to a temperature of 1373 K. The materials were additionally sulfated by standard methods and showed in contrast to sulfated bulk zirconia a lower catal) ic activity in the -butane isomerization. 

Preventol D 7 Preventol P109 Preventol P 109-N zinc primer paiits, anticorrosive Ethyl sHicale zirconia precursor Bacote20 ... 

The amorphous hydrous zirconia precursor particles that was then calcined to yield Zr02 nanoparticles CO2 Zirconyl nitrate hydrate, aqueous ammonia solution as a precipitating agent PFPE Not reported Particles formed from precursors synthesized atl5.3MPa 1 0-30 nm, quasispherical particles formed from precursors synthesized at [57]... 

A TEM Diflraction and Simulation Method for Early-Stage Studies of the Evolution of Gel-Derived Zirconia Precursors, J. Tong, J.M. Zuo and L. Eyring, J. Amer. Ceram. Soc., 76, 857-864 (1993). 

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